וַיְהִ֤י יִצְחָק֙ בֶּן־אַרְבָּעִ֣ים שָׁנָ֔ה בְּקַחְתּ֣וֹ אֶת־רִבְקָ֗ה בַּת־בְּתוּאֵל֙ הָֽאֲרַמִּ֔י מִפַּדַּ֖ן אֲרָ֑ם אֲח֛וֹת לָבָ֥ן הָאֲרַמִּ֖י ל֥וֹ לְאִשָּֽׁה׃
Исааку было сорок лет, когда он принял Ревекку, дочь Вифуила Арамейского, Паддан-Арама, сестру Лавана Арамейского, своей женой.
Or HaChaim
Kabbalists, of course, are aware that there are mystical dimensions which account for the emergence of Esau as a potentially wicked person, whereas it was Rebeccah's union with Isaac which was the cause of any pollutant disturbing her holiness. Rabbi Shimon ben Yochai is quoted in the Zohar (Sullam edition Chayey Sarah 251) as explaining that the reason the Torah describes Isaac as loving his wife Rebeccah, something that is natural and does not require special mention, is that the love of the male for the female is rooted in the "left" side of the emanations. in Isaac's case it was the fire of the גבורה, his predominant characteristic which stems from the "left side" of the emanations.. If the holiness of the two was tainted in any way this was due more to Isaac than to Rebeccah. Jacob's physical perfection is compared to that of Adam's before the sin, as we know from Baba Metzia 84. He did not therefore inherit any pollutant from his mother. Students of the Kabbalah will understand all this. [I have elaborated on the author's text to make it more intelligible for the non-kabbalist. Ed.] When we wrote earlier (25,20) that the reason that Esau was wicked was because Rebeccah had a wicked brother called Laban, this did not influence Rebeccah's character.
Ramban
SHALL A CHILD BE BORN TO HIM THAT IS A HUNDRED YEARS OLD? There is no wonder that a person who is a hundred years old should beget children, for men beget as long as they have vigor even if they be ninety years old or a hundred years old, even in these generations. All the more in the days of Abraham, who had not yet lived two thirds of his life.443Since Abraham lived 175 years (25:7) and was now only 100, he had not yet passed two-thirds of his life-span. So it is no wonder that he was yet in his vigor. Moreover, forty years after this, he begot many children from Keturah.444Further 25:1-2. “Forty years later.” Isaac was wed at the age of forty (25:20), and Abraham married Keturah after Isaac’s marriage (25:1). There was thus an interval of at least forty years between the time Abraham begot Isaac and when he begot children from Keturah. But Abraham’s saying, Shall a child be born to him that is a hundred years old, expressed this thought: Since he did not beget a child from this woman while he was young, how could he beget from her after he was a hundred and she ninety? He knew that her womanly periods had ceased. Therefore Abraham did not say so originally when he was told, And I will make nations of thee,445Above, Verse 6. but only when he was told that he would beget a child from Sarah.
Now He commanded him, And thou shalt call his name Isaac,446Verse 19 here. on account of the rejoicing done by Abraham, which is proof that it was out of faith and joy [that Abraham said, Shall a child be born, etc.]447As explained above. Had it been said out of a sense of derision, G-d would not have told him to call his son by a name which would commemorate his lack of faith. (Bachya.) And after Abraham called him so, as G-d had commanded him, Sarah said, “Is he not rightly named Isaac? For G-d hath made laughter for me.”448Further, 21:6.
Now He commanded him, And thou shalt call his name Isaac,446Verse 19 here. on account of the rejoicing done by Abraham, which is proof that it was out of faith and joy [that Abraham said, Shall a child be born, etc.]447As explained above. Had it been said out of a sense of derision, G-d would not have told him to call his son by a name which would commemorate his lack of faith. (Bachya.) And after Abraham called him so, as G-d had commanded him, Sarah said, “Is he not rightly named Isaac? For G-d hath made laughter for me.”448Further, 21:6.
Siftei Chakhamim
When marrying a woman he should investigate her brothers. However, Lavan the brother of Rivka (Bereishis 25:20), is mentioned only “in order to praise Rivkah.” This is because Yitzchok surely would not have investigated Lavan [to know about Rivkah]. Furthermore, [it is different with Rivkah because] there was no need for Scripture to mention her father, brother or birthplace, as all were mentioned before — forcing us to say that they all have a Midrashic meaning. (Re’m) And we cannot say that it indeed teaches us that one who contemplates marrying a woman should investigate all these factors. First of all, granted that investigating the woman’s brothers has a reason: [her children will probably resemble them] as most children resemble their mother’s brothers. But this is not true of her father, and certainly not of the people of her birthplace. Secondly, [if all of these factors should be investigated], why did Aharon only investigate Elisheva’s brother? We see that her father’s name is not mentioned — implying that Aharon investigated only her brother.